Not a Differential: Why "Is It ADHD or Trauma?" Is the Wrong Question
I recently presented at the Global ADHD Conference 2026 with a talk called Not a Differential: ADHD and Trauma as a Both/And. If you missed it, you can register and watch the recording at globaladhd.com. This is the written version for clinicians, with the key references at the end.
"Is it ADHD or is it trauma?" I get asked this by clinicians, teachers, parents and, lately, the internet allllllll the time. My answer: Often, it's both... with autism is frequently the third road at the same intersection.
The title is deliberately cheeky. Differential diagnosis matters enormously. But when we treat ADHD and trauma only as differentials, assessment becomes a contest with one winner, and that framing can cost people years of good, formulation-informed treatment.
The overlap is real, and rating scales can't untangle it
Inattention, restlessness, big emotions, poor sleep, social difficulty, sensory sensitivity, impulsivity, a negative view of self, and shutdowns that could be autistic overwhelm or dissociation - all of these symptoms sit in the shared middle of a diagnostic Venn Diagram. Rating scales pick up that middle well, because they ask what is happening, not why.
The distinguishing features live at the edges. ADHD starts early, shows up across settings, and attention tends to follow interest. Autistic differences in social communication are present from early childhood. Trauma responses usually (but not always) have a before and after, and track reminders: intrusions, avoidance, startle. But a Venn diagram isn't a sorting hat. People live in more than one circle.
"Both" is the base rate
A meta-analysis of 28 controlled studies found people with ADHD had nearly three times the risk of PTSD (Spencer et al., 2016).
A Swedish team compared people with ADHD with their own siblings, across more than two million people. Same family, same kitchen, same arguments about the same unpaid bills. The sibling with ADHD was still more than twice as likely to develop PTSD (Wendt et al., 2023).
On screening questionnaires, a third to nearly half of autistic adults report probable PTSD. Yet a 2025 meta-analysis found rates of formally diagnosed PTSD in autistic people no higher than the general population. The authors raised diagnostic overshadowing as a possible explanation: once someone has an autism diagnosis, distress gets put down to autism and nobody asks what happened. Trauma, therefore, gets missed. And when we consider how many autistic and/or ADHDers experience bullying or isolation, this diagnostic oversight is a huge concern.
The arrows run both ways, but they're not the same size
ADHD raises exposure to trauma. Some of it is mechanical: in a study of more than two million adults, crash risk with ADHD was about 1.5 times that of controls, and roughly 40 percent lower in the months people were taking ADHD medication (Chang et al., 2017). Some of it is social: children with ADHD are bullied more, and responsibility for that harm sits entirely with the people who cause it. And some of it is thousands of hours of being corrected, told off and called lazy. Those little-t-trauma experiences rarely meet PTSD criteria, but they're where beliefs like "I'm too much" or "I'm stupid" take root. Genetically informed analyses in the Swedish study found ADHD liability predicted PTSD, while PTSD liability didn't consistently predict ADHD.
Common Autistic and ADHD experiences also naturally widen what counts as traumatic. Bullying and exclusion are common, and years of masking can become a chronic social threat. When Rumball and colleagues asked autistic adults about their worst experiences, many wouldn't meet DSM Criterion A at all: humiliation, sensory overwhelm, losing a support worker or a pet, sudden change (Rumball, Happé & Grey, 2020).
The question as to whether trauma can cause ADHD is another real debate right now. Research suggests that an arrow in this direction CAN exist, but generally only in very specific circumstances. For example, severe early deprivation leaves a mark: children who spent more than six months in Romanian institutions showed persistent inattention and overactivity into adulthood (looking like ADHD), despite loving adoptive homes (Sonuga-Barke et al., 2017). Across quasi-experimental studies, maltreatment has a genuine but small causal effect on mental health (Baldwin et al., 2023), and a smaller effect on development of later ADHD. And here's the diagnostic catch that can make this difficult to unpiece: severe adversity before age three produces symptoms that comfortably meet ADHD's onset-before-12 rule, so age of onset alone won't separate them diagnostically.
Same symptom, same context - different driver?
Let's take a supermarket meltdown as an example. If it's autistic sensory overload, it will build with the noise and lights of the supermarket environment, and then ease when input drops. Noise-cancelling headphones can be life-changing for this person.
If it's a trauma cue, say the aftershave of the man in aisle four, the drivers for this meltdown are threat perception and meaning making. Headphones won't reduce the intensity of these symptoms - they are not EMDR.
And if it's ADHD overwhelm, maybe you came in for three things, the list is on the fridge where you forgot it, there are forty kinds of pasta and the self-checkout announces an unexpected item in the bagging area. That calls for a different external structure (notes on the phone?) and a little self-compassion.
One meltdown, three drivers, three different support options.
Four lenses for any symptom
Trying to unpiece the diagnostic question - or even just the treatment options (when we now assume that it is likely ADHD AND trauma - and probably also autism), can be tricky. Some of the questions and ideas I find helpful are below:
Onset: when did the issue/difficulty first appear, and was that before or after the adversity?
Driver: what reliably sets it off?
Modifier: what makes it better or worse? Safety, structure, sensory load, interest, medication?
Course: is it stable across settings and time, including the safe times, or does it rise and fall with threat, load or reminders?
A few questions I find especially useful in the room:
"When your mind goes, where does it go?" People with ADHD can usually tell you: "I started thinking about sharks" or "I just got distracted and did something else." Dissociation either has no content or is entirely in the past (flashback): "It's just gone" or "I went back there" Losing track is ADHD's middle name. Losing twenty minutes should make you curious about dissociation.
"Is it the same on holiday?" Safe but noisy and unfamiliar separates an autism response from a trauma response surprisingly often.
"What do you watch for in other people to suggest safety or danger?" A traumatised person will often answer instantly. Tone. The jaw. The sound of keys in the door.
Other points: Do the archaeology - take a history, get the old reports. Early school reports written before any known adversity are gold, and early medical experiences (NICU, surgery, a frightening birth) deserve the same routine questions as family history. Early surgery as a baby has a strong association with an ADHD diagnosis in later childhood, so it's really worth exploring here.
What changes in treatment
Once you know what you're dealing with, treatment becomes about formulation (as always!). Where can an ADHD coach best support outcomes in organisation and planning? And what difficulties actually need evidence-based trauma treatment. The questions above will help you choose your best approach.
ADHD medications are often the first line of support. Yet, surprisingly when trauma is recognised alongside ADHD, this is often not the case. A recent study by Baweja et al (2026) found that youth with ADHD and PTSD are clinically complex, with multiple comorbidities. They also found that clinicians appear to de-prioritize stimulants after PTSD diagnosis, despite evidence of superior clinical outcomes. Whilst it may be difficult to piece apart an ADHD symptom from PTSD, this is not a reason to stop prescribing - perhaps just monitor a longer list of symptoms and see what their effect is on sleep, nightmares and arousal.
Lastly - don't wait for calm to treat the trauma. For many neurodivergent clients, life never "settles", because the baseline includes ongoing sensory load, social load and masking. Emotional dysregulation may always be higher than a neurotypical population. Trauma-focused work can start sooner with adapted delivery and a supported environment:
Shorter segments of trauma therapy, visual structure, fidget toys, movement and reminders for ADHD
Explicit agendas, literal language, shorter processing time and a sensory-considered room for autistic clients
Interoception work before asking for distress ratings, since around half of autistic people have high alexithymia. Adapt your distress ratings to match interests or concrete ideas of increasing scale (e.g. weather ratings, noise scales etc).
Stabilisation that changes the environment, rather than teaching breathing and hoping it works ok
Involve family, friends and partners in the treament and ensure they can keep their 'outside therapy life' secure, safe and predictable as much as possible.
Three questions to take home
When did it start, and was that before or after the adversity?
What drives it, and what changes it?
What would we do differently if we got the driver right?
Dr Alice Morgan is a clinical psychologist and Clinical Director of Starling Health Collective in Melbourne, offering clinical supervision, EMDR consultation and trauma-informed professional development for health professionals.
Key references
Baldwin, J. R., et al. (2023). Childhood maltreatment and mental health problems: A systematic review and meta-analysis of quasi-experimental studies. American Journal of Psychiatry, 180(2), 117-126.
Baweja, R., et al. (2026). Treatment patterns and clinical outcomes in youth with comorbid ADHD and PTSD. Journal of Attention Disorders, 30(7), 872-886.
Chang, Z., et al. (2017). Association between medication use for ADHD and risk of motor vehicle crashes. JAMA Psychiatry, 74(6), 597-603.
Faraone, S. V., & Larsson, H. (2019). Genetics of attention deficit hyperactivity disorder. Molecular Psychiatry, 24(4), 562-575.
Rumball, F., Happé, F., & Grey, N. (2020). Experience of trauma and PTSD symptoms in autistic adults. Autism Research, 13(12), 2122-2132.
Sonuga-Barke, E. J. S., et al. (2017). Child-to-adult neurodevelopmental and mental health trajectories after early life deprivation. The Lancet, 389(10078), 1539-1548.
Spencer, A. E., et al. (2016). Examining the association between PTSD and ADHD: A systematic review and meta-analysis. Journal of Clinical Psychiatry, 77(1), 72-83.
Wendt, F. R., et al. (2023). The relationship of ADHD with PTSD: A two-sample Mendelian randomization and population-based sibling comparison study. Biological Psychiatry, 93(4), 362-369.
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